This is a 2 fold question.
First. I purchased a 2001 Malibu as a leftover. By 8,000 miles, I had to get the brakes done, and the rotors replaced. Since then, and keep in mind I only have 53,000 on the car, I have had the brakes done 5 times, and this is grocery store, kids to school driving. We were told that there was no defect or recal, but this doesn't seem right. Even with good pads, we only got 10,000 miles on the brakes, and this is the 3rd set of rotors. I read that lots of other people with Malibus have the same problems.
Second, there is a lower end knock. We add oil from time to time, but it seems to disappear, and there are no drips on the driveway, nor does the car burn oil that we can see. Where is my oil going and what would cause the knock?
And if you are looking for a used car, please stay away from Malibus. This has been a nightmare.